Refresh-EnvironmentVariables.ps1

<#PSScriptInfo

.VERSION 1.0.2

.GUID 9ff8b18d-cc46-449e-81f1-bbdacc3f41b4

.AUTHOR asherto

.COMPANYNAME asheroto

.TAGS PowerShell Windows refresh reload path env environment variable variables update current

.PROJECTURI https://github.com/asheroto/Refresh-EnvironmentVariables

.RELEASENOTES
[Version 0.0.1] - Initial Release.
[Version 1.0.0] - Total rework of script, implementing Chocolatey's Update-SessionEnvironment function into one single script.
[Version 1.0.1] - Rename to Refresh-EnvironmentVariables to avoid naming conflicts with Chocolatey's RefreshEnv.cmd.
[Version 1.0.2] - Fix bug with CheckForUpdate.

#>

<#
.SYNOPSIS
    Refreshes the environment variables in the current PowerShell session.
.DESCRIPTION
    Refreshes the environment variables in the current PowerShell session.
.EXAMPLE
	Refresh-EnvironmentVariables
.PARAMETER CheckForUpdate
    Checks if there is an update available for the script.
.PARAMETER Version
    Displays the version of the script.
.PARAMETER Help
    Displays the full help information for the script.
.NOTES
	Version      : 1.0.2
	Created by   : asheroto
.LINK
	Project Site: https://github.com/asheroto/Refresh-EnvironmentVariables
#>
[CmdletBinding()]
param (
    [switch]$Version,
    [switch]$Help,
    [switch]$CheckForUpdate
)

# Derived from the original work by Chocolatey Software, used in accordance with license
# Copyright © 2017 - 2021 Chocolatey Software, Inc.

# Changes made:
# - Extracted the functions from the original script for use in Refresh-EnvironmentVariables.ps1
# - Removed Write-FunctionCallLogMessage from Update-SessionEnvironment as it only applies to Chocolatey
# - Added custom functions

# Original license, included per the terms of the Apache 2.0 license:
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Version
$CurrentVersion = '1.0.2'
$RepoOwner = 'asheroto'
$RepoName = 'Refresh-EnvironmentVariables'
$PowerShellGalleryName = 'Refresh-EnvironmentVariables'

# Versions
$ProgressPreference = 'SilentlyContinue' # Suppress progress bar (makes downloading super fast)
$ConfirmPreference = 'None' # Suppress confirmation prompts

# Display version if -Version is specified
if ($Version.IsPresent) {
    $CurrentVersion
    exit 0
}

# Display full help if -Help is specified
if ($Help) {
    Get-Help -Name $MyInvocation.MyCommand.Source -Full
    exit 0
}

function Get-GitHubRelease {
    <#
        .SYNOPSIS
        Fetches the latest release information of a GitHub repository.

        .DESCRIPTION
        This function uses the GitHub API to get information about the latest release of a specified repository, including its version and the date it was published.

        .PARAMETER Owner
        The GitHub username of the repository owner.

        .PARAMETER Repo
        The name of the repository.

        .EXAMPLE
        Get-GitHubRelease -Owner "asheroto" -Repo "winget-install"
        This command retrieves the latest release version and published datetime of the winget-install repository owned by asheroto.
    #>
    [CmdletBinding()]
    param (
        [string]$Owner,
        [string]$Repo
    )
    try {
        $url = "https://api.github.com/repos/$Owner/$Repo/releases/latest"
        $response = Invoke-RestMethod -Uri $url -ErrorAction Stop

        $latestVersion = $response.tag_name
        $publishedAt = $response.published_at

        # Convert UTC time string to local time
        $UtcDateTime = [DateTime]::Parse($publishedAt, [System.Globalization.CultureInfo]::InvariantCulture, [System.Globalization.DateTimeStyles]::RoundtripKind)
        $PublishedLocalDateTime = $UtcDateTime.ToLocalTime()

        [PSCustomObject]@{
            LatestVersion     = $latestVersion
            PublishedDateTime = $PublishedLocalDateTime
        }
    } catch {
        Write-Error "Unable to check for updates.`nError: $_"
        exit 1
    }
}

function CheckForUpdate {
    param (
        [string]$RepoOwner,
        [string]$RepoName,
        [version]$CurrentVersion,
        [string]$PowerShellGalleryName
    )

    $Data = Get-GitHubRelease -Owner $RepoOwner -Repo $RepoName

    if ($Data.LatestVersion -gt $CurrentVersion) {
        Write-Output "`nA new version of $RepoName is available.`n"
        Write-Output "Current version: $CurrentVersion."
        Write-Output "Latest version: $($Data.LatestVersion)."
        Write-Output "Published at: $($Data.PublishedDateTime).`n"
        Write-Output "You can download the latest version from https://github.com/$RepoOwner/$RepoName/releases`n"
        if ($PowerShellGalleryName) {
            Write-Output "Or you can run the following command to update:"
            Write-Output "Install-Script $PowerShellGalleryName -Force`n"
        }
    } else {
        Write-Output "`n$RepoName is up to date.`n"
        Write-Output "Current version: $CurrentVersion."
        Write-Output "Latest version: $($Data.LatestVersion)."
        Write-Output "Published at: $($Data.PublishedDateTime)."
        Write-Output "`nRepository: https://github.com/$RepoOwner/$RepoName/releases`n"
    }
    exit 0
}

# Check for updates if -CheckForUpdate is specified
if ($CheckForUpdate) {
    CheckForUpdate -RepoOwner $RepoOwner -RepoName $RepoName -CurrentVersion $CurrentVersion -PowerShellGalleryName $PowerShellGalleryName
}

function Get-EnvironmentVariable {
    <#
.SYNOPSIS
Gets an Environment Variable.

.DESCRIPTION
This will will get an environment variable based on the variable name
and scope while accounting whether to expand the variable or not
(e.g.: `%TEMP%`-> `C:\User\Username\AppData\Local\Temp`).

.NOTES
This helper reduces the number of lines one would have to write to get
environment variables, mainly when not expanding the variables is a
must.

.PARAMETER Name
The environment variable you want to get the value from.

.PARAMETER Scope
The environment variable target scope. This is `Process`, `User`, or
`Machine`.

.PARAMETER PreserveVariables
A switch parameter stating whether you want to expand the variables or
not. Defaults to false.

.PARAMETER IgnoredArguments
Allows splatting with arguments that do not apply. Do not use directly.

.EXAMPLE
Get-EnvironmentVariable -Name 'TEMP' -Scope User -PreserveVariables

.EXAMPLE
Get-EnvironmentVariable -Name 'PATH' -Scope Machine

.LINK
Get-EnvironmentVariableNames

.LINK
Set-EnvironmentVariable
#>
    [CmdletBinding()]
    [OutputType([string])]
    param(
        [Parameter(Mandatory = $true)][string] $Name,
        [Parameter(Mandatory = $true)][System.EnvironmentVariableTarget] $Scope,
        [Parameter(Mandatory = $false)][switch] $PreserveVariables = $false,
        [parameter(ValueFromRemainingArguments = $true)][Object[]] $ignoredArguments
    )

    # Do not log function call, it may expose variable names
    ## Called from chocolateysetup.psm1 - wrap any Write-Host in try/catch

    [string] $MACHINE_ENVIRONMENT_REGISTRY_KEY_NAME = "SYSTEM\CurrentControlSet\Control\Session Manager\Environment\";
    [Microsoft.Win32.RegistryKey] $win32RegistryKey = [Microsoft.Win32.Registry]::LocalMachine.OpenSubKey($MACHINE_ENVIRONMENT_REGISTRY_KEY_NAME)
    if ($Scope -eq [System.EnvironmentVariableTarget]::User) {
        [string] $USER_ENVIRONMENT_REGISTRY_KEY_NAME = "Environment";
        [Microsoft.Win32.RegistryKey] $win32RegistryKey = [Microsoft.Win32.Registry]::CurrentUser.OpenSubKey($USER_ENVIRONMENT_REGISTRY_KEY_NAME)
    } elseif ($Scope -eq [System.EnvironmentVariableTarget]::Process) {
        return [Environment]::GetEnvironmentVariable($Name, $Scope)
    }

    [Microsoft.Win32.RegistryValueOptions] $registryValueOptions = [Microsoft.Win32.RegistryValueOptions]::None

    if ($PreserveVariables) {
        Write-Verbose "Choosing not to expand environment names"
        $registryValueOptions = [Microsoft.Win32.RegistryValueOptions]::DoNotExpandEnvironmentNames
    }

    [string] $environmentVariableValue = [string]::Empty

    try {
        #Write-Verbose "Getting environment variable $Name"
        if ($win32RegistryKey -ne $null) {
            # Some versions of Windows do not have HKCU:\Environment
            $environmentVariableValue = $win32RegistryKey.GetValue($Name, [string]::Empty, $registryValueOptions)
        }
    } catch {
        Write-Debug "Unable to retrieve the $Name environment variable. Details: $_"
    } finally {
        if ($win32RegistryKey -ne $null) {
            $win32RegistryKey.Close()
        }
    }

    if ($environmentVariableValue -eq $null -or $environmentVariableValue -eq '') {
        $environmentVariableValue = [Environment]::GetEnvironmentVariable($Name, $Scope)
    }

    return $environmentVariableValue
}

function Get-EnvironmentVariableNames([System.EnvironmentVariableTarget] $Scope) {
    <#
.SYNOPSIS
Gets all environment variable names.

.DESCRIPTION
Provides a list of environment variable names based on the scope. This
can be used to loop through the list and generate names.

.NOTES
Process dumps the current environment variable names in memory /
session. The other scopes refer to the registry values.

.INPUTS
None

.OUTPUTS
A list of environment variables names.

.PARAMETER Scope
The environment variable target scope. This is `Process`, `User`, or
`Machine`.

.EXAMPLE
Get-EnvironmentVariableNames -Scope Machine

.LINK
Get-EnvironmentVariable

.LINK
Set-EnvironmentVariable
#>

    # Do not log function call

    # HKCU:\Environment may not exist in all Windows OSes (such as Server Core).
    switch ($Scope) {
        'User' {
            Get-Item 'HKCU:\Environment' -ErrorAction SilentlyContinue | Select-Object -ExpandProperty Property
        }
        'Machine' {
            Get-Item 'HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Environment' | Select-Object -ExpandProperty Property
        }
        'Process' {
            Get-ChildItem Env:\ | Select-Object -ExpandProperty Key
        }
        default {
            throw "Unsupported environment scope: $Scope"
        }
    }
}

function Update-SessionEnvironment {
    <#
.SYNOPSIS
Updates the environment variables of the current powershell session with
any environment variable changes that may have occurred during a
Chocolatey package install.

.DESCRIPTION
When Chocolatey installs a package, the package author may add or change
certain environment variables that will affect how the application runs
or how it is accessed. Often, these changes are not visible to the
current PowerShell session. This means the user needs to open a new
PowerShell session before these settings take effect which can render
the installed application nonfunctional until that time.

Use the Update-SessionEnvironment command to refresh the current
PowerShell session with all environment settings possibly performed by
Chocolatey package installs.

.NOTES
This method is also added to the user's PowerShell profile as
`refreshenv`. When called as `refreshenv`, the method will provide
additional output.

Preserves `PSModulePath` as set by the process.

.INPUTS
None

.OUTPUTS
None
#>

    $userName = $env:USERNAME
    $architecture = $env:PROCESSOR_ARCHITECTURE
    $psModulePath = $env:PSModulePath

    #ordering is important here, $user should override $machine...
    $ScopeList = 'Process', 'Machine'
    if ('SYSTEM', "${env:COMPUTERNAME}`$" -notcontains $userName) {
        # but only if not running as the SYSTEM/machine in which case user can be ignored.
        $ScopeList += 'User'
    }

    foreach ($Scope in $ScopeList) {
        Get-EnvironmentVariableNames -Scope $Scope |
        ForEach-Object {
            Set-Item "Env:$_" -Value (Get-EnvironmentVariable -Scope $Scope -Name $_)
        }
    }

    #Path gets special treatment b/c it munges the two together
    $paths = 'Machine', 'User' |
    ForEach-Object {
      (Get-EnvironmentVariable -Name 'PATH' -Scope $_) -split ';'
    } |
    Select-Object -Unique
    $Env:PATH = $paths -join ';'

    # PSModulePath is almost always updated by process, so we want to preserve it.
    $env:PSModulePath = $psModulePath

    # reset user and architecture
    if ($userName) {
        $env:USERNAME = $userName;
    }
    if ($architecture) {
        $env:PROCESSOR_ARCHITECTURE = $architecture;
    }
}

# Output
Write-Output "Refreshing environment variables..."

# Call the function to update the session environment
Update-SessionEnvironment

# Output
Write-Output "Finished"